Samson 3725 - Technical data

EB 8394 EN 21
Design and principle of operation
3.4 Technical data
Type3725 Positioner
Travel (adjustable) Direct attachment to Type 3277: 5 to 30 mm
Direct attachment to Type 2780-2: 6/12/15 mm
Attachment to Type3372 Actuator: 15/30 mm
Attachment according to IEC60534-6 (NAMUR): 5 to 50 mm
Attachment to rotary actuators: 24 to 100°
Reference variable w
(reverse polarity protection)
Static destruction limit
4 to 20 mA signal range · Two-wire device
Split-range operation 4 to 11.9 mA and 12.1 to 20 mA
±33 V
Minimum current 3.8 mA
Load impedance Max. 6.3V
Supply air
Air quality acc. to
ISO8573-1
Supply air: 1.4 to 7bar (20 to 105psi)
Max. particle size and density: Class 4 · Oil content: Class 3 · Pressure dew point:
Class 3 or at least 10K below the lowest ambient temperature to be expected
Signal pressure (output) 0 bar up to the supply pressure · Can be limited to approx. 2.3bar by software
Characteristic 3 characteristics for globe valves · 9 characteristics for rotary valves
Hysteresis ≤ 0.3 %
Sensitivity ≤ 0.1 %
Transit time Only for actuators with initialization time > 0.5 s
1)
Direction of action w/x reversible
Air consumption ≤ 100 l
n
/h with a supply pressure up to 6bar and a signal pressure of 0.6bar
Air output capacity
To ll actuator with air At Δp 6bar: 8.5 m
n
³/h At Δp = 1.4bar: 3.0m
n
³/h, K
Vmax
(20 °C) = 0.09
To vent actuator At Δp 6bar: 14.0m
n
³/h At Δp = 1.4bar: 4.5m
n
³/h, K
Vmax
(20 °C) = 0.15
Permissible ambient
temperature
–20 to +80 °C
–25 to +80 °C with metal cable gland
The limits in the test certicates additionally apply for explosion-protected versions
1)
For faster actuators, a volume restriction must be used. Otherwise, the initialization cannot be performed
successfully.